Method of making paper and fiber board



UNITED STATES PATENT OFFICE.

ALBERT L. CLAIPP, 0F DANVERS, MASSACHUSETTS.

METHOD OF MAKING PAPER AND FIBER BOARD.

No Drawing. A Applicationv filed June 23,

To allwho mz'tmay concern.

Be it known that I, ALBERT L. CLAPP, a citizen. of the United States, residing at Danvers, in the county of Essex and State of Massachusetts, have invented new and useful Improvements in Methods of Making Paper and Fiber Board, of which the following is a specification.

This invention has relation to the manu facture of a fibrous material which may be employed for the production of paper as fiber board or analogous products.

In the manufacture of beet sugar, a residual waste or pressed pulp remains, which comprises fiber or cellular material, proteid, and other organic substances, and this pulp constitutes one of the essential ingredients or component raw materials employed in the process which I shall describe.

I have discovered that when beet pulp is digested in an aqueous solution of sodium carbonate, under heat and pressure, more or less of the proteid is dissolved, and may be precipitated by means of a suitable agent such as aluminum sulfate, to constitute a size for fibrous materials. I have further found that if this digestion takes place in the presence of the fibrous material, the dissolved proteid will permeate the fibers of such material, and may subsequently be precipitated therein and thereon.

As an example of my process, I may cite the following:

, 1000 parts by weight of cotton fiber, mechanical or chemical wood pulp or other suitable oellulosic material; 500 parts of pressed beet pulp; 50 parts of sodium carbonate; and sufiicient water to cover the mass, are loaded into a digester, and the cover thereof is closed. Steam is injected from time to time to cook the mass at about fifteen pounds pressure for about two hours, care beingtaken not to prolong the cooking sufficiently to injure the cellulose fibers of the beet pulp. During this digestion certain proteid constitutents of the beet pulp go into solution and are cooked into the cellulose fibers. Then the contents of the digester are withdrawn and delivered to a beating engine, with additional water, if necessary, to insure a free circulation of the stock in the beater. The beating action is contin ed until the stock has been suffi- Specification ofLetters Patent.

Patented Sept. 6, 1921.

1920. Serial No. 391,162.

'ciently reduced and disintegrated, and then aluminum sulfate is added and beaten into the mass to cause precipitation of the dissolved proteid in and on the fibers. The stock may now be formed into sheets by the aid of any suitable paper making or Web forming machine. When the materials are supplled to the digester in the proportions hereinbefore recited, I usually form the web in convo-lutions on the suction cylinder of a wet machine, until a sheet is formed, of a predetermined caliper, which is then slit, removed and dried, and, if desired, subjected to pressure. The sheet material thus producedis horny, hard and relatively inflexible,presenting somewhat the appearance of very hard fiber board. If desired, sodium resinate may be supplied to the beater before the introduction of the aluminum sulfate, and the proportion of the latter increased to cause the recipitation of aluminum resina-te on. the bers and thus further size the stock.

If it is desired to produce a flexible web or sheet of paper, the proportion of beet pulp furnished to the digester should be decreased.

- What I claim is 1. A process which comprises digesting beet pulp with heat and pressure in the presence of an aqueous solution of sodium carbonate, to dissolve certain constituents thereof, and then precipitating the same with a precipitating agent.

2. A process which comprises digesting cellulosic material and beet pulp with heat and pressure in the presence of sodium carbonate, and then precipitating dissolved constituents of the beet pulp in and on the cellulose fibers.

3. A process which comprises digesting cotton fibers and beet pulp with heat and pressure in the presence of sodium carbonate, and then precipitating dissolved constituents of the beet pulp in and on the cotton fibers.

i. process which comprises cooking cellulose fibers and beet pulp in a sodium carbonate solution under pressure in a closed digester, then subjecting the mass to a disintegrating operation, and then adding a precipitating agent to precipitate certain dissolved constituents of the beet pulp.

5. A process which comprises cooking cellulose fibers and beet pulp in a sodium carfibers and a sizing compound which is prebonate solution under pressure in a closed cipitated from the soluble constituents of 1( digester, then subjecting the mass to a disbeet pulp digested with heat and pressure integrating operation, then adding a prein the presence of sodium carbonate.

5 cipitating 'agent to precipitate certain dis- In testimony whereof I have afiixed my solved constituents of the beet pulp, and signature. finally. forming the pulped mass into a sheet.

6. A fibrous material comprising cellulose ALBERT L. CLAPP. 

